Low-dose arsenic exposure in Bangladesh: Findings from the Health Effects of Arsenic Longitudinal Study

Chronic arsenic exposure through drinking water has become a growing public health issue affecting millions of people worldwide, including 35 to 77 million in Bangladesh and nearly 15 million in the United States. Inorganic arsenic is a class I human carcinogen, and puts exposed individuals at increased risk of skin and other arsenic-induced cancers, as well as cardiovascular, pulmonary and other non-malignant disorders. As part of the Columbia University Superfund Research Program, we established the Health Effects of Arsenic Longitudinal Study (HEALS)—a large prospective cohort study based on individual-level data among a population exposed to a wide range of inorganic arsenic from drinking water in Araihazar, Bangladesh. Over the past ten years, using a population-based sampling frame, we recruited over 20,000 men and women (with >97% response rates) and collected detailed questionnaires, clinical data, and biospecimen samples from them at baseline and biennially thereafter. Through a dedicated medical clinic, established for the project, we have also developed an effective mechanism of following the cohort, especially for detecting incidence and mortality of dermatological, pulmonary, and cardiovascular disorders. We have prospectively evaluate the effects of various measures of arsenic exposure, including effects at the low-dose range, on the incidence of skin lesions, mortality from chronic disease, as well as other health outcomes. These findings will be discussed with an emphasis on the low-dose exposure range.